wrt300n: virtual wireless possible without vlan support?

hi - i've got a few wrt300n (V1) routers around. they have great antennae and signal for b/g/n devices, but are limited by 4mb rom space and lack of vlan support (although corerev=11 so may be capable).

i want to set up wireless 'repeaters': wireless ethernet bridges with AP on virtual wireless adapter. (yes, i know this slows down transfers)

when i try to configure these on shibby build 121 (tomato-ND-1.28.5x-121-VPN.trx) , the router freezes before i'm done configuing (usuallly when i switch from 'gateway' to 'router' mode) , requiring hard reset.

is this limitation a result of lack of vlan support? do i need 2 vlans for a repeater? (i had both wireless adapters on the lan bridge). why would that be different from have two separate bridges and tying them together?